UWL: Screening and Assessment Methods (2009)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:

To evaluate the clinical usefulness of the MNA to identify malnutrition in elderly patients with cognitive impairment.

Inclusion Criteria:
  • Elderly patients with cognitive impairment admitted to a geriatric convalescence unit (intermediate care facility)
  • Cognitive impairment was considered when Mini-Mental State Examination scores were below 21.
Exclusion Criteria:

None specifically mentioned.

Description of Study Protocol:

Recruitment

Recruitment methods not described.

Design

Cross-sectional study.

Statistical Analysis

  • The analyzed population was divided into four quartiles of the MNA scores: Very low (under 13.5), low (between 13.5 and 16), intermediate (between 16 and 18.5) and high (over 18.5)
  • Likelihood ratios for each MNA quartile were obtained by dividing the percentage of patients in a given MNA category who were undernourished (according to the American Institute of Nutrition) by the percentage of patients in the same MNA who were not undernourished.
Data Collection Summary:

Timing of Measurements

MNA and nutritional evaluation were performed at admission.

Dependent Variables

Diagnosis of malnutrition.

Independent Variables

  • Mini Nutritional Assessment (MNA)
  • Nutritional evaluation, according to the sequential model of the American Institute of Nutrition. According to the criteria, malnutrition was considered if there were abnormalities in at least one of the following parameters: Albumin, cholesterol, BMI and brachial circumference.
  • Functional status assessed by the Barthel Index
  • Comorbidity assessed by the Charlson Index.
Description of Actual Data Sample:
  • Initial N: 63 patients with cognitive impairment (47 women and 16 men)
  • Attrition (final N): 63 patients
  • Age: Mean, 80.1±8.1 years
  • Ethnicity: Not mentioned
  • Location: Spain.
Summary of Results:

Likelihood Ratios for the MNA Quartiles and their Clinical Impact Values

Variables

Undernourished

Not Undernourished

Likelihood Ratio

Clinical Impact Value

Number

27
36
 
 

Very Low (<13.5)

14 (73.6%)

5 (26.3%)

2.79

High 

Low (>13.5 and <16)
6 (33.3%)
12 (66.7%)
0.49
Low
Intermediate (>16 and <18.5)
6 (50.0%)
6 (50.0%)
1.00
Indeterminate
High (>18.5)
1 (7.1%)
13 (92.8%)
0.07
Very low

Other Findings

  • Based on the American Institute of Nutrition, 27 patients (42.8%) proved to be undernourished at admission and 36 (57%) were well-nourished
  • Based on the original MNA scores, 39 patients (61.9%) were undernourished, 23 (36.5%) were at risk of malnutrition and one (1.5%) was well-nourished
  • In the very-low MNA quartile, the likelihood ratio was 2.79 and for the low MNA quartile, it was 0.49.
  • For intermediate and high MNA categories, likelihood ratios were 1.0 and 0.07, respectively.
Author Conclusion:
  • As a conclusion of the present study, we can say that undernourishment has a high prevalence among patients with cognitive impairment admitted to a geriatric convalescence unit
  • In the present study, the diagnostic capacity of the MNA has been evaluated by means of the likelihood ratios. In this way, we can conclude that the MNA instrument identified undernourished patients with a high clinical diagnostic impact value only when very-low scores (<13.5) were obtained (likelihood ratio greater than 1.0).
  • For the other categories, likelihood ratios were either low or indeterminate, which means that these categories are less useful as a means of identifying undernourished patients in our setting. This low clinical diagnostic impact value can be explained by the high prevalence of malnutrition risk factors present in elderly patients discharged from an acute care hospital, especially those factors associated with functional status, which result in an overestimation of undernourishment, when only MNA is applied.
Funding Source:
Other: Not reported
Reviewer Comments:
  • Recruitment methods, inclusion criteria and exclusion criteria were not well-described
  • Statistical analysis was not well-described.
Quality Criteria Checklist: Primary Research
Relevance Questions
  1. Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies) Yes
  2. Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about? Yes
  3. Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice? Yes
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) Yes
 
Validity Questions
1. Was the research question clearly stated? Yes
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? Yes
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? Yes
  1.3. Were the target population and setting specified? Yes
2. Was the selection of study subjects/patients free from bias? ???
  2.1. Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study? No
  2.2. Were criteria applied equally to all study groups? N/A
  2.3. Were health, demographics, and other characteristics of subjects described? Yes
  2.4. Were the subjects/patients a representative sample of the relevant population? ???
3. Were study groups comparable? N/A
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) N/A
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? N/A
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) N/A
  3.4. If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis? N/A
  3.5. If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.) N/A
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? N/A
4. Was method of handling withdrawals described? Yes
  4.1. Were follow-up methods described and the same for all groups? Yes
  4.2. Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? N/A
  4.5. If diagnostic test, was decision to perform reference test not dependent on results of test under study? N/A
5. Was blinding used to prevent introduction of bias? ???
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? N/A
  5.2. Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.) ???
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? ???
  5.4. In case control study, was case definition explicit and case ascertainment not influenced by exposure status? N/A
  5.5. In diagnostic study, were test results blinded to patient history and other test results? N/A
6. Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described? Yes
  6.1. In RCT or other intervention trial, were protocols described for all regimens studied? N/A
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? Yes
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? N/A
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? N/A
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? N/A
  6.6. Were extra or unplanned treatments described? N/A
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? N/A
  6.8. In diagnostic study, were details of test administration and replication sufficient? N/A
7. Were outcomes clearly defined and the measurements valid and reliable? Yes
  7.1. Were primary and secondary endpoints described and relevant to the question? Yes
  7.2. Were nutrition measures appropriate to question and outcomes of concern? Yes
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? N/A
  7.4. Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures? Yes
  7.5. Was the measurement of effect at an appropriate level of precision? Yes
  7.6. Were other factors accounted for (measured) that could affect outcomes? Yes
  7.7. Were the measurements conducted consistently across groups? N/A
8. Was the statistical analysis appropriate for the study design and type of outcome indicators? ???
  8.1. Were statistical analyses adequately described and the results reported appropriately? No
  8.2. Were correct statistical tests used and assumptions of test not violated? ???
  8.3. Were statistics reported with levels of significance and/or confidence intervals? No
  8.4. Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)? N/A
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? ???
  8.6. Was clinical significance as well as statistical significance reported? Yes
  8.7. If negative findings, was a power calculation reported to address type 2 error? N/A
9. Are conclusions supported by results with biases and limitations taken into consideration? ???
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? No
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? No
  10.2. Was the study free from apparent conflict of interest? Yes